Cave discoveries hint at how modern humans outlasted Neanderthals

Archaeologists report evidence about the transition from Neanderthals to modern humans, found in a cave excavation in the Czech Republic.

A suspected speartip made from material sourced more than 100km east of the cave. Photo: Miroslav Kralík

Archaeologists researching a cliffside cave site in the Czech Republic have discovered evidence of stone tools and suspected spear tips, suggesting Neanderthals and modern humans occasionally travelled through the area 28,000 to 50,000 years ago.

The findings add a missing piece to the puzzle concerning events during the Middle-Upper Palaeolithic transition. This is when Neanderthals went extinct – for reasons that are still hotly debated – and modern humans first arrived.

“We found a small number of stone tools which told an incredible story about the high levels of human mobility at the time. Over thousands of years, people were using this cave for short stopovers and they came from many different directions, as the raw materials that these tools were made from indicate,” said Dr Nejman.

Excavation recovered stone artefacts, a bone ornament, a small stone blade, charcoal, and many different bones of extinct cave bears. Bones of other extinct animals including reindeer, auroch, wild horse and woolly rhinoceros were also found.

“The raw material was often obtained 100km to 200km away so these people were not living in one place for long, but walking long distances, possibly in search for game or raw materials to make their tools,” said Dr Nejman.

A team of researchers from Australia and the Czech Republic investigatedhow people lived in this harsh glacial landscape and what the physical environment and climate was like.

Dr Ladislav Nejman of the University of Sydney outside Pod Hradem Cave, in the Moravian Karst region of the Czech Republic. Photo: Petr Skrdla

New sediment ancient DNA technology in use

An analysis conducted by Dr Rachel Wood from the Australian National University (ANU) incorporated a recently developed improvement to radiocarbon dating, using Accelerator Mass Spectrometry, where the pre-treatment of samples is able to give a precise timeline for the numerous human visits to the cave.

“Such a relatively precise timeline for such an old site would be unthinkable even 10 to 20 years ago,” said Dr Nejman.

“We also gleaned a lot of information about the climate, the plants that grew around the cave, the type of wood that people brought into the cave to make fires and even what they ate.”

A pine nut from the Swiss Pine – which is now extinct in the area because the climate is too warm – was roasted and consumed by somebody in the cave between 45,000 to 48,000 years ago. The researchers hope to learn if it was a Neanderthal or a modern human who roasted the pine, through an emerging technique called sediment aDNA (ancient DNA).

Analysing sediment aDNA can work out what type of animals and humans visited the cave, even without their bones.

The vertebrae of a cave bear discovered by archaeologists. Photo: Dr Ladislav Nejman

Investigating if different species overlapped

Dr Nejman said: “The most significant thing we found in a 2011 excavation of the cave is a unique bone bead – probably part of a necklace – that is a testament to the incredible skill and exquisite craftsmanship these people possessed.”

Dr Duncan Wright of ANU said: “We can tell by the artefacts that small groups of people camped at this cave. This was during glacial periods suggesting they were well adapted to these harsh conditions. It’s quite possible that the two different species of humans met in this area.”

“Neanderthals had a tendency to live in one place and although we know they had very high levels of physical activity, they tended to return to the same place most of the time. In contrast, modern humans tended to move their place of residence much more frequently,” said Dr Nejman.

He added: “This difference in residential mobility levels probably helped the modern humans to survive in this harsh environment, because they could meet more often with other groups, reducing inbreeding.”

Pod Hradem Cave is located in the Moravian Karst region of the Czech Republic, 20km outside the second largest city, Brno.